The Swedish personal identity number: possibilities and pitfalls in healthcare and medical research

Age-related cardiovascular disease in Down syndrome: A population-based matched cohort study

BACKGROUND

Life expectancy for individuals with Down syndrome (DS) has increased dramatically. To improve detection and prevention, the risk of age-related cardiovascular disease in this population needs to be better defined.

METHODS

We performed a population-based matched cohort study. Through the National Patient Register (NPR) and/or the Medical Birth Register, we identified all individuals born in Sweden between 1946 and 2000 with a diagnosis of DS. Each individual with DS was matched to 50 comparators by sex, birth year, and county of birth. Data on ischemic and hemorrhagic stroke, acute myocardial infarction (AMI), and covariates indicating cardiovascular risk were retrieved from the NPR. Associations between DS and cardiovascular outcomes were estimated using Cox proportional hazards models. We also assessed the influence of cardiovascular risk factors.

RESULTS

We included 5155 individuals with DS, of which 55% were male. The median age at the end of follow-up was 35 in the DS population and 42 among the comparisons. DS was associated with increased risk of ischemic stroke (hazard ratios [HR] 4.41, 95% confidence intervals [CI] 3.53-5.52) and hemorrhagic stroke (HR 5.14, 95% CI 3.84-6.89). The overall risk of AMI was similar in DS and comparators but increased in young individuals with DS. The risk of ischemic stroke was elevated in individuals with DS with selected atherosclerotic (HR 12.67, 95% CI 7.04-22.78) as well as embolic (HR 10.35, 95% CI 6.69-16.01) risk factors, as compared to comparators without risk factors.

CONCLUSION

Individuals with DS were at increased risk of cardiovascular outcomes.

The relative age effect on antidepressant use in children and adults

BACKGROUND

Having young relative age in school is an identified risk factor for depression among schoolchildren, but it is unclear if this risk remains in adulthood. This study aimed to investigate the association between young relative age in school and antidepressant use across different age groups.

METHOD

This population-based study used data from the Swedish Medical Birth Register and the Prescribed Drug Register combined with data from Statistics Sweden. The population of 3,575,510 subjects, (48.6 % female), was split into different age groups, with groups spanning from 0 to 7 years of age to 40-45 years of age. The odds ratios (OR) of antidepressant use in the first as compared to the fourth birth-quarters, was determined by logistic regression.

RESULTS

Young relative age was positively associated with use of antidepressants with an OR of 1.05 (95 % confidence interval, 1.05-1.06) in the study population. This association was significant in all age groups that had started school and remained among adults.

LIMITATIONS

Data on indication for antidepressant medication prescription was unavailable, some subjects might have had antidepressants for other disorders then anxiety and depression. Another limitation is that it is unclear when during schooling children were accelerated/deferred. Moreover, antidepressant medication is uncommon among small children.

CONCLUSION

This study shows that young relative age within the school year increases the prevalence of antidepressant use in all investigated age-groups that had started school, long after the end of schooling.

Health-related quality of life across heart failure categories: associations with clinical characteristics and outcomes

AIMS

The study aims to examine characteristics and outcomes associated with health-related quality of life (HRQoL) in patients with heart failure (HF) with preserved, mildly reduced and reduced ejection fraction (EF) (HFpEF, HFmrEF and HFrEF).

METHODS AND RESULTS

Data on HRQoL were collected in the Swedish Heart Failure Registry (SwedeHF; 2000-2021) using the EuroQoL 5-dimensional visual analogue scale (EQ 5D-vas). Baseline EQ 5D-vas scores were categorized as 'best' (76-100), 'good' (51-75), 'bad' (26-50) and 'worst' (0-25). Independent associations between patients' characteristics and EQ 5D-vas, as well as between EQ 5D-vas and outcomes were assessed. Of 40 809 patients (median age 74 years; 32% female), 29% were in the 'best', 41% in the 'good', 25% in the 'bad' and 5% in the 'worst' EQ 5D-vas categories, similarly distributed across all EF categories. Higher New York Heart Association (NYHA) class was strongly associated with lower EQ 5D-vas regardless of EF categories, followed by chronic obstructive pulmonary disease, smoking, body mass index, higher heart rate, anaemia, previous stroke, ischaemic heart disease, use of diuretics and living alone, whereas higher income, male sex, outpatient status and higher systolic blood pressure were inversely associated with lower EQ 5D-vas categories. Patients in the 'worst' EQ 5D-vas category as compared with the 'best' had the highest risk of all-cause death [adjusted hazard ratios 1.97, 95% confidence interval (CI) 1.64-2.37 in HFrEF, 1.77, 95% CI 1.30-2.40 in HFmrEF and 1.43 95% CI 1.02-2.00 in HFpEF].

CONCLUSIONS

Most patients were in the two highest EQ 5D-vas categories. Higher NYHA class had the strongest association with lower EQ 5D-vas categories, across all EF categories. Patients in the worst EQ 5D-vas category were at the highest risk of mortality.

Craniomaxillofacial trauma increases the risk of temporomandibular joint disorders and days of work disability-a SWEREG-TMD registry-based study

Although craniomaxillofacial (CMF) trauma is a factor recognized as contributing to the development of temporomandibular joint disorders (TMJD), large population-based research on CMF trauma and subsequent TMJD is lacking. Additionally, it is unknown how previous CMF trauma affects work disability reimbursements for patients with TMJD (pwTMJD). This Swedish registry-based study included 33,315 pwTMJD matched to 333,122 individuals from the general population. Both a case-control design and a cohort design were used in this study to evaluate the association between CMF trauma and TMJD, and to investigate how CMF trauma impacts the number of days on work disability among pwTMJD. The main study finding was that many types of previous CMF trauma were strongly associated with TMJD, with mandibular fractures having the strongest association (adjusted odds ratio 11.4). Furthermore, the strongest association for an increased number of annual days on work disability was found for pwTMJD with a history of CMF trauma. These results suggest that CMF trauma influences the developmental path of TMJD, even in a population-based sample.

Predictors of preschool attention-deficit/hyperactivity disorder diagnosis: a population-based study using national registers

BACKGROUND

The diagnosis of attention-deficit/hyperactivity disorder (ADHD) in preschool years (before age 6 years) is a marker of severity and poor prognosis. This study investigated a broad range of predictors of ADHD diagnosis during preschool age.

METHODS

Population-based cohort study using Swedish registers. The final sample consisted of all children born in Sweden between 2001 and 2007 who could be linked to both of their biological parents, excluding those who died or emigrated (n = 631,695). Follow-up was completed December 31, 2013. Cox proportional-hazards models for survival analysis were used to identify the predictors that increased the risk of receiving a clinical diagnosis of ADHD from 3 to 5 years. Hazard ratios (HR) with 95% confidence intervals (CI) were presented for each of the 41 selected predictors covering early-onset psychiatric comorbidities, nonpsychiatric medical conditions, parental history and perinatal factors.

RESULTS

At the end of follow-up, 1,686 preschoolers (2.7% of the whole sample) had received a diagnosis of ADHD. We found that 39 out of 41 predictors were associated with increased risk of a later diagnosis of preschool ADHD. Novel associations with preschool ADHD diagnosis were found for gastroesophageal reflux disease (HR = 3.48), premature contractions during pregnancy (HR = 2.03), and criminal conviction history from any parent (HR = 2.14).

CONCLUSIONS

A large number of novel and well-established predictors of preschool ADHD diagnosis were identified. This broad set of early predictors may direct future clinical research and assist in early identification of preschool ADHD.

Association between bullying victimization and obsessive-compulsive disorder: a population-based, genetically informative study

The extent to which bullying victimization is associated with an increased risk of obsessive-compulsive disorder (OCD) has received little empirical attention. This longitudinal, population-based, genetically informative study examined whether self-reported bullying victimization at age 15 was associated with a clinical diagnosis of OCD in the Swedish National Patient Register and with self-reported obsessive-compulsive symptoms (OCS) at ages 18 and 24 in 16,030 twins from the Child and Adolescent Twin Study in Sweden. Using a discordant twin design, including monozygotic (MZ) and dizygotic (DZ) twins, each twin was compared with their co-twin, allowing a strict control of genetic and environmental confounding. At the population level, adjusting for birth year and sex, each standard deviation (SD) increase in bullying victimization was associated with a 32% increase in the odds of an OCD diagnosis (OR, 1.32; 95% CI, 1.21-1.44), of 0.13 SD in OCS at age 18 (β, 0.13; 95% CI, 0.11-0.16), and of 0.11 SD in OCS at age 24 (β, 0.11; 95% CI, 0.07-0.16). While associations tended to persist in the within DZ-twin comparison models, the estimates attenuated and were no longer statistically significant in the within MZ-twin comparisons. These results suggest that the association between bullying victimization and OCD/OCS is likely due to genetic confounding and therefore incompatible with a strong causal effect. Other mechanisms, such as evocative gene-environment correlations, are more plausible explanations for the observed associations.

Incidence and prevalence of granulomatosis with polyangiitis in Sweden, 2006-2019, a register-based study

OBJECTIVE

To investigate incidence and prevalence of granulomatosis with polyangiitis (GPA) in Sweden nationwide between 1 January 2006 until 31 December 2019 in a register-based study including the entire Swedish population.

METHOD

In the population-based National Patient Register (NPR) we identified patients with incident and prevalent GPA during the period 2006-2019. Age- and sex standardized annual incidence and crude period prevalence were estimated. Results were stratified on age, sex, and season.

RESULTS

We identified 2013 individuals with incident GPA during the study period. Median age was 63 years (IQR 51-72) and 46 % were women. The mean standardized incidence was 1.9 per 100,000 person-years (95 % CI 1.8-2.0), with a slightly higher incidence in men 2.0 (95 % CI 1.9-2.2) than in women 1.7 (95 % CI 1.6-1.8). We noted the highest incidence in the group aged 70-79, 4.1 (95 % 3.7-4.5). The annual incidence remained stable over the study period range 1.7-2.0. We could not find any seasonal variation in incidence. The point prevalence on December 31st, 2019, was 25.4 per 100,000 (95 % CI 24.3-26.5) based on the 2132 individuals we identified as prevalent. The period prevalence increased from 18.7 per 100,000 (95 % CI 17.8-19.1) in 2006-2010 to 23.9 per 100,000 (95 % CI 22.8-25.0) in 2016-2019.

CONCLUSION

Our estimates show that incidence of GPA has been stable over the period 2006-2019 in Sweden which are in line with published data from southern Sweden. The prevalence increased during the study period which could be due to improvement in treatment leading to an increased survival.

Does socioeconomic status influence the choice of surgical technique in abdominal rectal cancer surgery?

AIM

This study aimed to estimate the impact of socioeconomic status on the probability of receiving open (OPEN) or minimally invasive surgery (MIS) for curative abdominal rectal cancer resection.

METHODS

All patients diagnosed with rectal cancer clinical Stage I-III during the period 2010-2021 who underwent curative abdominal resection surgery, MIS or OPEN, were included. Patients were identified in the Colorectal Cancer Database, a register-linkage based on the Swedish Colorectal Cancer Register and linked to several national Swedish health-related and demographic registers. Socioeconomic factors, sex, patient and tumour characteristics, number of previous surgical procedures and category of hospital were collected. Exposures were level of education (categorized as 6-9, 10-12, >12 years), household income (quartiles 1-4) and country of birth (Sweden, Nordic countries outside Sweden, Europe outside the Nordic countries, outside Europe), and outcome was MIS or OPEN. Multivariable logistic regression models were fitted for each exposure, adjusted for age, sex, cT and cN, level of tumour, and number of previous abdominal surgical procedures.

RESULTS

A total of 13 778 patients were included of whom 43.6% underwent MIS (n = 6007) and 56.4% OPEN (n = 7771). Highest level of education (OR for highest vs. lowest level of education 1.15; 95% CI 1.03-1.29) and highest household income quartile (OR for highest vs. lowest household income quartile 1.27; 95% CI 1.12-1.44) increased the likelihood of receiving MIS.

CONCLUSION

Despite the tax-financed healthcare system in Sweden, rectal cancer patients with the highest level of education and the highest household income had an increased probability of receiving MIS.

Adolescent cardiorespiratory fitness and risk of cancer in late adulthood: A nationwide sibling-controlled cohort study in Sweden

BACKGROUND

Cardiorespiratory fitness has been linked to both lower and higher risks of cancer, but the evidence comes from observational analysis which may be influenced by unobserved confounders and bias processes. We aimed to examine the associations between adolescent cardiorespiratory fitness and risk of cancer in late adulthood while addressing the unknown influence of unobserved familial confounders and diagnostic bias processes.

METHODS AND FINDINGS

We conducted a sibling-controlled cohort study with registry linkage based on all Swedish men who participated in mandatory military conscription examinations from 1972 to 1995 and who completed standardized cardiorespiratory fitness testing. The outcomes were overall cancer diagnosis and cancer mortality, and 14 site-specific cancers (diagnosis or death), ascertained using the National Patient Register and Cause of Death Register until 31 December 2023. A total of 1,124,049 men, including 477,453 full siblings, with a mean age of 18.3 years at baseline, were followed until a median (maximum) age of 55.9 (73.5) years, during which 98,410 were diagnosed with cancer and 16,789 died from cancer (41,293 and 6,908 among full siblings respectively). In cohort analysis, individuals in the highest quartile of fitness had a lower risk of overall cancer mortality (adjusted hazard ratio [HR]: 0.71, 95% confidence interval [CI] 0.67, 0.76; P < 0.001) compared to the lowest quartile, corresponding to a standardized cumulative incidence (1-Survival) difference of -0.85 (95% CI [-1.00, -0.71]) percentage points at 65 years of age. Individuals in the highest quartile of fitness also had lower risks (HRs ranging from 0.81 to 0.49, incidence differences ranging from -0.13 to -0.32 percentage points; P < 0.001 for all) of rectum, head and neck, bladder, stomach, pancreas, colon, kidney, liver, bile ducts, and gallbladder, esophagus, and lung cancer. Yet, individuals in the highest quartile of fitness had higher risks of prostate (HR: 1.10, 95% CI [1.05, 1.16]; P < 0.001, incidence difference: 0.48 percentage points, 95% CI [0.23, 0.73]) and skin cancer (e.g., non-melanoma HR: 1.44, 95% CI [1.38, 1.50]; P < 0.001, incidence difference: 1.84 percentage points, 95% CI [1.62, 2.05]). Individuals in the highest quartile of fitness had a higher risk of overall cancer diagnosis (HR: 1.08, 95% CI [1.06, 1.11]; P < 0.001, incidence difference: 1.32 percentage points, 95% CI [0.94, 1.70]), results driven by prostate and skin cancer being the most common types of cancer. When comparing full siblings, and thereby controlling for unobserved shared confounders, the lower risk of overall cancer mortality remained (HR: 0.78, 95% CI [0.68, 0.89]; P < 0.001, incidence difference: -0.61 percentage points, 95% CI [-0.93, -0.28]), while the excess risk of prostate (HR: 1.01, 95% CI [0.90, 1.13]; P = 0867, incidence difference: 0.05 percentage points, 95% CI [-0.50, 0.60]), skin (e.g., non-melanoma HR: 1.09, 95% CI [0.99, 1.20]; P = 0.097, incidence difference: 0.40 percentage points, 95% CI [-0.07, 0.87]), and overall cancer diagnosis (HR: 1.00, 95% CI [0.95, 1.06]; P = 0.921, incidence difference: 0.04 percentage points, 95% CI [-0.80, 0.88]) attenuated to the null. For other site-specific cancers, sibling comparisons results varied, with more attenuation for melanoma, kidney, stomach, bladder, pancreas, and liver, bile ducts, and gallbladder cancer, while associations with lung, colon, head and neck, and esophagus cancer seemed to attenuate less. The findings were confirmed through an extensive set of sensitivity analyses. The main limitations of this study include the lack of inclusion of female participants, lack of data on other risk factors such as smoking, alcohol consumption, and physical activity, and only adjustment for the unobserved confounders which are shared between full siblings.

CONCLUSIONS

Higher levels of adolescent cardiorespiratory fitness were associated with lower overall cancer mortality in late adulthood, a finding that persisted in sibling comparisons. However, the influence of unobserved familial confounding appeared to vary by cancer type and be more pronounced for cancer diagnoses than for mortality. This may suggest a need for robust causal methods to triangulate results, rather than relying on correlations alone, to better inform public health efforts.

Grandmaternal obesity in early pregnancy and risk of grandoffspring preterm birth: a nationwide three-generation study

OBJECTIVE

Obesity in pregnancy increases risk of preterm birth (PTB), a leading cause of infant mortality and morbidity. The heritability of obesity suggests associations of grandmaternal obesity with grandoffspring outcomes, but a potential effect on PTB has not been interrogated. We studied whether grandmaternal (F0 generation) body mass index (BMI) in early pregnancy was related to grandoffspring (F2 generation) PTB risk by type, and to maternal (F1 generation) preeclampsia risk.

METHODS

Among 315,240 singleton live-born infants from a countrywide three-generation Swedish cohort, we compared risks of spontaneous and medically indicated PTB, defined as gestational age <37 completed gestation weeks, between categories of maternal grandmaternal BMI in early pregnancy. We also interrogated associations of grandmaternal BMI categories with risk of maternal preeclampsia, a major cause of medically indicated PTB. We assessed whether the associations were mediated through consequences of obesity. In a subset, we examined associations with paternal grandmaternal BMI. To address unmeasured confounding by shared familial factors, we assessed the associations of parental full sisters' BMI with PTB.

RESULTS

Maternal grandmaternal obesity (BMI ≥ 30.0) was related to increased risks of grandoffspring medically indicated PTB and maternal preeclampsia, compared with normal BMI. Adjusted hazard and risk ratios (95% confidence intervals) were, respectively, 1.54 (1.28, 1.86) and 1.32 (1.16, 1.49). Maternal sisters' BMI was unrelated to PTB or preeclampsia risks. Maternal obesity or preeclampsia mediated most (85%) of the maternal grandmaternal obesity-grandoffspring medically indicated PTB association, whereas the association with maternal preeclampsia was primarily mediated (61%) through maternal obesity. There were no associations with spontaneous PTB. Paternal grandmaternal obesity was unrelated to grandoffspring's PTB risk.

CONCLUSION

Medically indicated PTB in grandoffspring is associated with maternal grandmaternal obesity.

A Longitudinal Post-authorization Safety Study of Golimumab in Treatment of Ulcerative Colitis: A Cohort Study in Denmark and Sweden, 2013-2021

BACKGROUND

When golimumab (GLM) was approved for the treatment of moderate to severe ulcerative colitis (UC) in 2013, a post-authorization safety study was conducted.

OBJECTIVE

Our objective was to examine whether exposure to GLM was associated with an increased incidence of all-cause total colectomy, colorectal cancer, and hepatosplenic T-cell lymphoma in Denmark and Sweden.

METHODS

We conducted a new-user, active comparator cohort study of patients with UC in 2013-2021. Exposure to GLM, other anti-tumor necrosis factor (TNF) agents (infliximab and adalimumab) and thiopurines was a time-varying variable. Therapies were based on prescription redemptions and hospital-based administration of medications from national prescription and hospital registers. The association between exposure to study therapies and outcomes was evaluated using Poisson regression of incidence rates (IRs), presented as IR ratios (IRRs) and 95% confidence intervals (CIs).

RESULTS

A total of 5177 and 7469 patients were included in Denmark and Sweden, respectively. The IR of all-cause total colectomy per 1000 person-years was higher in Denmark (IR 42.6; 95% CI 38.9-46.2) than in Sweden (IR 16.1; 95% CI 14.2-18.0). No significant difference was observed in all-cause total colectomy between GLM and other anti-TNF agents (Denmark: adjusted IRR [aIRR] 1.28; 95% CI 0.98-1.66; Sweden: aIRR 1.17; 95% CI 0.72-1.90). A significant difference was observed between GLM and thiopurines (Denmark: aIRR 13.62; 95% CI 8.73-21.26; Sweden: aIRR 4.52; 2.75-7.41). Privacy regulations prevented analysis of a few colorectal cancer events. No hepatosplenic T-cell lymphoma events were identified.

CONCLUSION

The IR of all-cause total colectomy with GLM was similar to that with other anti-TNF agents but was much higher than with thiopurines, probably related to confounding by indication.

Increased risk of osteoporotic fractures and osteoporosis in patients with Addison's disease in Sweden: A nationwide population-based cohort study

BACKGROUND

The risk of major osteoporotic fractures (MOFs) and osteoporosis in patients with autoimmune Addison's disease (AAD) is unclear.

OBJECTIVE

To investigate the risk of MOF in patients with AAD and the possible correlation with adrenal hormone replacement doses.

METHODS

Swedish national health registers were used to identify 1869 subjects with AAD and 16,844 matched controls. The primary outcome was MOF, and the secondary outcome was treatment with osteoporosis medications. Marginal Cox models were used to compare time-to-event outcomes. The study period spanned from 1 July 2005 until 31 December 2020. Individuals at risk were followed from inclusion until censored or the end of the study period.

RESULTS

A total of 77 patients with AAD (7.1/1000 person-years [PY]), and 387 matched controls (3.9/1000 PY) were diagnosed with MOF. The risk of MOF was higher in patients with AAD compared to matched controls, with an adjusted hazard ratio (aHR) of 1.82 (95% confidence interval [CI], 1.41-2.35) and increased in both male and female patients, with aHR of 2.51 (95% CI, 1.56-4.02) and 1.65 (95% CI, 1.22-2.24), respectively. Patients with AAD had an increased risk of treatment with osteoporosis medications: aHR 3.25 (95% CI, 2.71-3.99), compared to controls. No significant differences in MOF rates were observed between patients treated with intermediate or high doses of glucocorticoids compared to low doses (p = 0.967 and p = 0.580, respectively). Similarly, stratification by mineralocorticoid dose (<0.10 vs. ≥0.10 mg/day) showed no significant association regarding MOF (p = 0.915).

CONCLUSIONS

The risk of MOF is increased in patients with AAD without any apparent correlation to adrenal hormone replacement doses.

Clinical Features of Myocardial Infarction in Women With a History of Preeclampsia: A Population-Based Cohort Study

BACKGROUND

Preeclampsia is associated with an increased lifetime risk of myocardial infarction. This study explored whether there is a difference in the clinical features and severity of myocardial infarction in women with previous preeclampsia compared with women with no history of preeclampsia.

METHODS

This register-based cohort study combined data from the Swedish Medical Birth Register with data from the quality register the Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies. Women with a first singleton birth between 1973 and 2019 were included. The outcome of myocardial infarction was categorized as severe if it resulted in death within 7 days, cardiogenic shock, cardiac arrest, impaired left ventricular systolic function, mechanical complication, or ST-segment-elevation myocardial infarction. The association between preeclampsia and myocardial infarction was investigated using cause-specific hazard models.

RESULTS

Among 1 966 096 women with a first singleton birth, 82 980 (4.2%) had preeclampsia. Myocardial infarction was registered in 10 758 (0.5%) of the total population. One-third (n=3672, 34.1%) of myocardial infarctions had severe features and two-thirds (n=6996, 69.1%) were nonsevere. Preeclampsia was associated with increased risk of myocardial infarction, with an adjusted hazard ratio (HR) of 1.71 (95% CI, 1.50-1.94) for severe and 1.86 (95% CI, 1.71-2.04) for nonsevere myocardial infarction. Myocardial infarction in women with prior preeclampsia compared with women without preeclampsia was associated with a higher risk of death (HR, 3.00 [95% CI, 1.10-8.14]), cardiogenic shock (HR, 1.69 [95% CI, 1.11-2.58]), and impaired left ventricular systolic function (HR, 1.69 [95% CI, 1.11-2.58]), while no association was observed for cardiac arrest (HR, 1.37 [95% CI, 0.98-1.93]), ST-segment-elevation myocardial infarction (HR, 1.01 [95% CI, 0.86-1.18]), or mechanical complication (HR, 0.57 [95% CI, 0.08-4.15]).

CONCLUSIONS

Women with a history of preeclampsia have almost twice the risk of myocardial infarction. Myocardial infarction among women with prior preeclampsia more often results in death, cardiogenic shock, and impaired left ventricular systolic function than among women without preeclampsia.

Adult-onset inflammatory bowel disease and the risk of venous thromboembolism - a Swedish nationwide cohort study 2007-2021

BACKGROUND

Earlier studies, mainly prior to the widespread use of advanced therapy and implementation of guidelines for thromboprophylaxis indicate a doubled risk of venous thromboembolism (VTE) in patients with inflammatory bowel disease (IBD).

METHODS

Using Swedish healthcare registers, we identified a population-based cohort of patients with incident IBD 2007-2021. Patients were matched by age, sex, calendar year of birth and place of residence with up to 10 reference individuals. The primary outcome was VTE, i.e., pulmonary embolism (PE) and deep vein thrombosis (DVT). Incidence rates (IRs) per 1000 person-years, cumulative incidence and hazard ratios (HRs) were calculated for IBD overall and according to clinical characteristics. The temporal trend of the incidence of VTE by calendar year was presented.

RESULTS

We followed 55,252 IBD patients and 536,067 reference individuals, for a median of 6.5 years. The incidence of VTE in IBD was 5.03 vs. 2.35 per 1000 person-years among reference individuals, corresponding to a doubled risk of VTE (HR = 2.12; 95% confidence interval [CI] 2.02-2.23). Particularly high risks were seen in the first year of follow-up, and among patients with extensive ulcerative colitis (UC), primary sclerosing cholangitis (PSC), extraintestinal manifestations, perianal disease and hospitalization at diagnosis. The occurrence of VTE in IBD did not decrease across calendar years.

CONCLUSIONS

IBD remains linked to an elevated risk of VTE, particularly with disease characteristics associated with a higher inflammatory burden and higher age. Our findings underscore the importance of continuous vigilance and individual assessment of VTE risk in patients with IBD.

Statin Use is Associated with a Less Severe Disease Course In Inflammatory Bowel Disease: A Nationwide Cohort Study 2006-2020

BACKGROUND

Statins reduce the risk of inflammatory bowel disease (IBD), however their effect on IBD disease progression is largely unknown.

METHODS

We linked Swedish healthcare registers and performed a nationwide cohort study (2006-2020) of 19 788 adults (≥18 years) with ulcerative colitis (UC) and 12 582 with Crohn's disease (CD). Of these, 1733 with UC and 962 with CD were identified as incident statin users after UC or CD diagnosis. After 1:1 propensity score matching, we compared statin users with non-users to estimate the risk of IBD-related surgery, hospitalizations, and disease flares expressed as incidence rates (IRs) and multivariable-adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs). For outcomes with statistically significant estimates, we calculated the numbers needed to treat (NNT).

RESULTS

During a median follow-up of 3.4 years we observed a reduced risk of IBD-related surgery in statin users (UC, IR: 3.4 [95%CI: 2.1-4.8] per 1000 person-years; CD, IR: 9.2 [6.2-12.2]) compared with non-users in UC (IR: 6.3 [4.2-8.5]; aHR: 0.55 [0.31-0.97]) and CD (IR: 15.4 [11.0-19.7]; aHR: 0.54 [0.33-0.88]). The NNT to avoid one IBD-related surgical event per year of statin treatment were 345 (UC) and 161 (CD). For statin users, the risks of hospitalizations (IR: 17.0 [13.9-20.2]; aHR: 0.68 [0.51-0.91]) and disease flares (IR: 207.4 [193.2-221.6]; aHR: 0.86 [0.77-0.97]) were reduced in UC, but not in CD (IR: 20.3 [15.8-24.9]; aHR: 0.78 [0.56-1.09] and IR: 245.5 [223.9-267.1]; aHR: 1.02 [0.88-1.19]). In UC, NNT for hospitalizations and disease flares were 145 and 15.

CONCLUSIONS

Statins were associated with a reduced risk of IBD-related surgery, hospitalizations, and disease flares in patients with UC, and with a reduced risk of IBD-related surgery in patients with CD.

Sickness absence > 14 days following mild traumatic brain injuries from traffic accidents: a Swedish nationwide register study

BACKGROUND

Mild traumatic brain injuries (mTBI), including concussions, following traffic accidents is common. How often these injuries lead to sickness absence (SA) among working aged individuals is however insufficiently studied. Thus, the aim of this study was to examine frequency of new SA following mTBI sustained in a road traffic environment and its associations with sociodemographic and injury-related factors.

METHOD

Nationwide population-based register study. Working aged individuals (18-63), living in Sweden, who in 2014 to 2016 acquired an mTBI in a traffic accident were included based on in- and specialised out-patient health care records. Information on SA (> 14 days), disability pension, pre-injury factors (age, sex, education, marital status, type of living area, country of birth, income from work) as well as injury-related factors (type of road user, in- or outpatient health care) were used in analyses of risk factors for a new SA-spell. Odds ratios (ORs), both crude and adjusted, with 95% confidence intervals (CIs) were estimated with logistic regression.

RESULTS

6073 individuals were identified. 12% had a new SA spell after injury. Sociodemographic risk factors were female sex, older age and being born outside Sweden. Car occupants had higher ORs for new SA, compared to pedestrians, bicyclists, and other road users, and was also associated with longer duration spells (> 90 days). Having received in-patient health care was associated with an OR of 3.7 for new SA compared to those only receiving out-patient health care (including emergency department visits). Having received in-patient health care was also associated with longer duration spells.

CONCLUSION

A traffic related mTBI is most often a benign injury, seldom resulting in a new SA spell of longer duration. When it does, it is more likely to involve car occupants, and those who have required in-patient health care.

Suspected de novo heart failure in outpatient care: the REVOLUTION HF study

BACKGROUND AND AIMS

Ambulatory patients presenting with signs or symptoms of heart failure (HF) should undergo natriuretic peptide testing. Rates of death, HF hospitalization, and healthcare costs were examined in patients thus identified with suspected de novo HF.

METHODS

This population-based study (REVOLUTION HF) encompassing two large healthcare regions in Sweden examined patients who presented to outpatient care for the first time between 1 January 2015 and 31 December 2020, who had a recorded sign (peripheral oedema) or symptom (dyspnoea) of HF, and whose N-terminal pro-B-type natriuretic peptide (NT-proBNP) measured >300 ng/L within ±30 days of that sign or symptom. Characteristics, outcomes, healthcare patterns, and healthcare costs for these patients were followed for 1 year. Comparisons were made with matched controls without history of HF, its signs, its symptoms, or elevated NT-proBNP.

RESULTS

Overall, 5942 patients (median age 78.7 years; 54% women) presented with suspected de novo HF. Within 1 year, 29% had received a HF diagnosis. Patients with suspected de novo HF had higher rates of all-cause death (11.7 vs. 6.5 events/100 person-years) and HF hospitalizations (12.5 vs. 2.2 events/100 person-years) than matched controls (n = 2048), with the highest event rates in the weeks after presentation. Rates were higher with higher NT-proBNP levels. Although some patients already used HF guideline-directed medical therapies for other indications, initiation of new medications was variable. Healthcare costs were higher in patients with suspected de novo HF than in matched controls, driven mostly by HF and chronic kidney disease.

CONCLUSIONS

Patients with suspected HF and elevated NT-proBNP had high mortality and morbidity in the weeks after presentation, and accrued substantial healthcare costs, highlighting an urgent need for prompt identification, evaluation, and treatment of HF.

Sickness absence among blue-collar workers in the retail and wholesale industry during the COVID-19 pandemic; a longitudinal cohort study

Sickness absence (SA) changed in various occupations during the COVID-19 pandemic. The aim was to investigate the prevalence of all-cause sickness absence (SA) during the COVID-19 pandemic in relation to in the preceding years, as well as factors associated with all-cause SA and SA due to COVID-19 and COVID-like diagnoses during the COVID-19 pandemic among blue-collar workers in the retail and wholesale industry. A population-based longitudinal cohort study using microdata linked from nationwide registers in Sweden. All 297 378 blue-collar employees aged 18-67 years in wholesale and retail in 2019 were followed during 2016-2021 regarding SA in spells > 14 days. Yearly prevalence rates were calculated for all-cause SA in sociodemographic and occupational groups. Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI) for all-cause SA and SA due to COVID-19 or COVID-like diagnoses in 2020 and 2021. The annual prevalences of SA were 7.5-8% in 2016-2018, 10% in 2020, and 9% in 2021. The prevalence of SA due to COVID-19 or COVID-like diagnoses was 2.1% in 2020 and 1.6% in 2021. The OR was higher in the older age groups (OR age 55-64 = 2.38, 95% CI 2.20-2.57 compared to age 25-34). There were few significant occupational differences, however, warehouse and terminal staff had a higher OR (1.37, 1.27-1.48) than sales assistants, daily goods. While SA rates increased during the COVID-19 pandemic, the distribution of SA between sociodemographic or occupational groups did not change markedly. The distribution of SA due to COVID-19 and COVID-like diagnoses was similar to all-cause SA.

Barriers and motivators associated with COVID-19 vaccination-a vaccine acceptance scoring system based on a population survey in southern Sweden

Low vaccination coverage against SARS-CoV-2 (COVID-19) is a public health concern. The aim of this study was to identify barriers and motivators associated with COVID-19 vaccination and develop a vaccine acceptance scoring system. From the overall population residing in Skåne county Sweden in 2022 (n = 1 384 531), 3600 randomly selected individuals (aged ≥18 years) received a survey. Questions were grouped into six domains reflecting trust in vaccines and institutions, benefit-risk balance, injunctive and descriptive norms and accessibility. Responses were scored as either assenting (1 p) or dissenting (0 p) in relation to its domain. A score between 1 and 5 p was constructed for each domain and a total vaccine acceptance score was analysed. Internal consistency overall and within domains was assessed with Cronbach's alpha. Associations with vaccination status and vaccine acceptance scores in relation to domains were modelled with logistic regression. 820 responses were received, 646 vaccinated (response rate 36%), and 174 unvaccinated (response rate 10%), with relatively high internal consistency overall (α = 0.76). Domains markedly associated with vaccination were injunctive norms OR 5.06 (95% CI 3.27, 7.83), descriptive norms OR 2.64 (1.63, 4.30) and trust in vaccines OR 1.66 (1.15, 2.40). Vaccine acceptance was measured with sufficient reliability in a Swedish population. Norms, in this context, general perceptions of acceptable/unacceptable behaviours and notion on actual performed behaviours, were together with trust in vaccines most strongly associated with vaccination. Future pandemic responses should consider these aspects in communication strategies and targeted interventions to increase and equalize vaccination uptake.

Swedish national cohort of children living with long-term respiratory support (DISCOVERY-P): cohort profile

PURPOSE

Children living with respiratory support rely on medical technology, either fully or partially, throughout the day to meet their breathing requirements. Although children and young people living with respiratory support at home undergo long-term treatments and make extensive use of health and social care services, there is a notable absence of comprehensive outcome data on this group. The establishment of the first nationwide Course of DISease reported to the Swedish CPAP Oxygen and VEntilator RegistrY paediatrics cohort aims to investigate the disease trajectory, clinical and socioeconomic risk factors influencing incident illness, hospitalisation risk and mortality among children living with respiratory support.

PARTICIPANTS

Data on patients aged 0-18 years reported to the Swedish National Registry for Respiratory Failure and Sleep Apnoea (Swedevox) 1 January 2015 to 29 July 2021 were merged with seven quality or governmental registries, the National Quality Registry for Intensive Care, the National Medical Birth Register, the Swedish Cause of Death Registry, the Registry for Interventions under the Act on Support and Service to Certain Disabled Persons, the Swedish National Patient Registry and with socioeconomic data from Total Population Registry and Longitudinal Integrated Database for health insurance and labour market studies.

FINDINGS TO DATE

The cohort includes 716 children, 59% male, who began respiratory support at an average age of 6.4 years (SD 5.4). Among them, 28% use continuous positive airway pressure, 64% long-term mechanical ventilation (LTMV), 3% high-flow oxygen therapy (HFOT) and 5% other methods. Respiratory support is mostly used at night, but many LTMV (54%) and HFOT (81%) users need daytime aid. 77% of LTMV users rely on mask connection, differing from international data.

FUTURE PLANS

Future projects include exploring the impact of socioeconomic factors on hospitalisation rates and mortality. The dataset is due for an update in 2026.

Phosphatidylethanol levels distinguish steatotic liver disease subgroups and are associated with risk of major liver outcomes

BACKGROUND & AIMS

Phosphatidylethanol (PEth) is an ethanol metabolite used as a specific biomarker for recent alcohol consumption. We aimed to determine the proportion of patients with or at risk for metabolic dysfunction-associated steatotic liver disease (MASLD) who had PEth levels indicative of harmful alcohol consumption, and to assess associations between PEth levels and the risk of major adverse liver outcomes (MALOs).

METHODS

We conducted a cohort study involving persons tested for PEth in Stockholm, Sweden between 2012 and 2020 (N=46,406), including patients with various steatotic liver disease (SLD) subtypes and individuals without SLD. Cumulative incidences of MALOs were calculated for the different groups while accounting for competing risk. Cox regression was used to evaluate the association between baseline PEth levels and the incidence of MALOs.

RESULTS

Among 6,377 patients with presumed MASLD, 1,294 (20%) had baseline PEth levels between 0.05 and 0.30 μmol/L (35-210 ng/ml), indicating excessive alcohol intake (MetALD), while 854 patients (13%) had values >0.30 μmol/L, indicating alcohol-related liver disease (ALD). Patients with MASLD and PEth levels between 0.05-0.30 μmol/L had similar median FIB-4 scores and cirrhosis prevalence as those with MASLD and PEth levels <0.05 μmol/L. However, patients with PEth levels between 0.05-0.30 μmol/L had higher cumulative incidences of MALOs compared to those with PEth levels <0.05 μmol/L. Elevated PEth levels were significantly linked to higher rates of MALOs in patients without cirrhosis, even after adjustments for age, sex, SLD subtype, and FIB-4 score. Patients with ALD had the highest PEth levels and worst prognosis.

CONCLUSIONS

PEth is a valuable alcohol biomarker for distinguishing between SLD subtypes, especially ALD, and predicts adverse outcomes in people with and without SLD.

IMPACT AND IMPLICATIONS

There is controversy regarding the various proposed steatotic liver disease (SLD) subtypes, the most recent definition suggesting that patients with an elevated alcohol consumption and MASLD should be classified as having MetALD. Here, we address this challenge by classifying patients with SLD by utilizing the biomarker phosphatidylethanol (PEth), a direct and reliable biomarker for recent alcohol consumption. Our analysis of this large cohort-comprising 46,406 patients-revealed that using the objective PEth biomarker may be a valuable tool for distinguishing between MASLD and MetALD, and that PEth is strongly associated with the risk of liver outcomes in individuals with and without known SLD. Integrating PEth testing into routine diagnostic evaluations could enhance knowledge on the underlying pathophysiology in SLD, reduce the potential for misclassification, and ultimately improve patient outcomes by enabling clinicians to offer appropriate therapies. Further research is needed to validate these findings in other populations and to explore the potential integration of PEth into broader clinical guidelines for managing SLD.

Changing patterns in joint replacement surgery in the hand in Sweden: a population-based study of 5382 patients

Over a 16-year period (2008-2023), data from the Swedish National Patient Register reveal shifting trends in operation for hand joint replacements linked to demographic, healthcare and surgical advances. Among 5382 identified cases, 63% were women, with the incidence peaking in the 65-74 age bracket, highlighting a marked gender gap in middle and older age groups. Regional analyses indicate significant disparities, as Örebro and Halland had rates exceeding 10 per 100,000, while Stockholm and Blekinge fell below 5 per 100,000. The adoption of total prostheses without cement declined by 22%, reflecting changing surgical preferences. Predictive modelling anticipates an overall decline in incidence by 2035, with gender-specific rates converging over time. These findings highlight the need for targeted healthcare policies that address inequities and minimize unwarranted variations in treatment. Standardized care programmes that support evidence-based surgical decision-making could reduce the incidence of both over- and under-treatment.Level of evidence: III.

All-cause and Cause-specific Mortality in Achalasia: A Nationwide Matched Cohort Study

BACKGROUND & AIMS

Achalasia has been linked to increased mortality, but evidence from large population-based cohorts is scarce. We aimed to assess mortality in individuals with achalasia.

METHODS

This nationwide cohort study included all adults in Sweden with incident achalasia (n = 704; 1969-2017; follow-up until December 31, 2021) without any other prior esophageal conditions. Achalasia was defined through International Classification of Disease codes in the Swedish National Patient Register in individuals who underwent endoscopic esophageal examination including biopsy as recorded in the histopathology cohort ESPRESSO. Individuals with achalasia were matched by age, sex, birth year, and county to up to 5 reference individuals (n = 3348) from the general population. In a secondary analysis, full siblings were used as secondary reference individuals. Mortality incidence rates (IRs) and multivariable-adjusted hazard ratios (aHRs) with 95% confidence intervals [Cis] for all-cause and cause-specific mortality were calculated using Cox proportional hazards modeling.

RESULTS

During a median follow-up of 9.1 years, there were 270 deaths in individuals with achalasia, and 1023 in reference individuals (IR, 69.4 vs 51.9/1000 person-years). This corresponded to a 1.42-fold increased risk of death (95% CI, 1.21-1.65); or 1 extra death per every 6 individuals with achalasia followed for 10 years. Risk increases were seen for death from any cancer (IR, 17.4 vs 11.8; aHR, 1.65; 95% CI, 1.21-2.23), esophageal cancer (IR, 2.7 vs 0.2; aHR, 23.19; 95% CI, 3.27-164.55), and respiratory disease (IR, 7.4 vs 3.9; aHR, 2.22; 95% CI, 1.28-3.87), but not from cardiovascular disease (IR, 22.7 vs 19.6; aHR, 1.10; 95% CI, 0.84-1.45). Results remained robust across sensitivity analyses, including sibling comparisons.

CONCLUSIONS

Individuals with achalasia had a 42% increased mortality rate compared with the general population. The elevated mortality risk indicates a need for long-term follow-up.

Risk of hepatic decompensation or HCC is similar in patients with ALD- and MASLD-cirrhosis: A population-based cohort study

BACKGROUND

It is unclear if the risk of hepatic decompensation or hepatocellular carcinoma (HCC) differs between patients with compensated alcohol-related liver disease (ALD)- and metabolic dysfunction-associated steatotic liver disease (MASLD)-cirrhosis. We investigated the risk to develop hepatic decompensation or HCC based on ALD or MASLD as the underlying etiology of cirrhosis.

METHODS

All patients with a new diagnosis in hospital-based outpatient care of ALD- or MASLD-cirrhosis in Sweden between 2002 and 2020 were identified using national registers. Hepatic decompensation was analyzed as a composite outcome with HCC. Cox regression was employed to compare rates of hepatic decompensation or HCC, and subsequent death.

RESULTS

1660 patients with ALD-cirrhosis and 943 patients with MASLD-cirrhosis were identified. The median ages were 64 years (IQR 57-70) and 69 years (IQR 62-75) in patients with ALD- and MASLD-cirrhosis, respectively. Patients with ALD-cirrhosis consisted of 69.4 % males, compared to 47.6 % males in the MASLD-cirrhosis group. 581 (35 %) patients with ALD-cirrhosis and 284 (30 %) patients with MASLD-cirrhosis developed hepatic decompensation or HCC (median follow-up time: 25 months), resulting in an adjusted hazard ratio of 1.12 (ALD- vs. MASLD-cirrhosis, 95 %-confidence interval=0.88-1.41). The adjusted risk of mortality afterwards was lower in patients with ALD-cirrhosis compared to patients with MASLD-cirrhosis (adjusted hazard ratio 0.62, 95 %-confidence interval=0.39-0.97).

CONCLUSIONS

The risk of hepatic decompensation or HCC is comparable in patients with ALD- and MASLD-cirrhosis, but the risk of mortality after a decompensation event or HCC tends to be higher in patients with MASLD-cirrhosis.

Sick Leave due to Stress and Subsequent Cancer Risk, a Swedish National Registry Study of 516,678 Cancer Cases

BACKGROUND

This study examined whether sick leave due to severe stress (stress leave) and duration of leave are associated with future cancer risk.

METHODS

We conducted a matched case-control study using complete-population data from Swedish national registers (2005 to 2018), including 516,678 primary cancer cases and 2,357,433 matched controls. Odds ratios (OR) were calculated by conditional logistic regression and adjusted for pre-specified confounders.

RESULTS

Stress leave of any duration, reported to the Swedish Social Insurance Register, was associated with a slightly increased cancer risk, with the highest risk estimate for 1-30 versus 0 days (adjusted OR 1.05, 95% CI 1.02-1.09). In men, a clear exposure-response trend was present. We observed increased risks of prostate cancer (adjusted OR for > 90 days: 1.10, 95% CI 1.01-1.20) and cervical cancer (adjusted OR for > 90 days: 1.11, 95% CI 1.05-1.17, including cancer in situ). In etiology-based analyses, a positive association was found for smoking-related cancers, and the risk relationship for non-cervical HPV-related cancers was similar to that for cervical cancer. Risk estimates were above one for several types of stress in relation to overall cancer risk, including an exposure-response trend for acute stress reactions (p-trend 4.0 × 10-4) but a null association for post-traumatic stress disorder.

CONCLUSIONS

Stress leave was associated with a modestly higher risk of cancer overall and prostate and cervical cancers specifically. Regardless of whether the link is biological or reflective of lifestyle mediators or for cervical cancer, lower participation in screening, these findings suggest a potential relevance of severe stress for cancer prevention.

Biomarkers for Prediction of Alcohol-Related Liver Cirrhosis: A General Population-Based Swedish Study of 537,250 Individuals

BACKGROUND AND AIMS

The study sought to examine which biomarkers have the best predictive capabilities for future alcohol-related liver cirrhosis (ARLC) in a general population setting.

METHOD

This population-based cohort study includes approximately 35% of the inhabitants of Stockholm County who had left a blood sample at an outpatient visit in primary care or occupational health screening from 1985 to 1996. All subjects with a blood sample measurement of alanine aminotransferase and aspartate aminotransferase (AST) were included, exclusions were made for persons with known liver disease. We ascertained incident ARLC by linkage to Swedish national health registers between to the end of 2011. Associations between biomarkers and incident ARLC were analyzed with Cox regression models and discrimination was assessed using C-statistics.

RESULTS

In all, 537,230 adult subjects were included. The mean age was 45 years and 53% were men. During a mean follow-up of 19.0 years, 2725 (0.51%) subjects developed ARLC. The biomarkers with the highest discrimination (C-index) for incident ARLC at 5 years were: AST (0.89), mean corpuscular volume (0.88), and γ-glutamyltransferase (0.81). Scoring systems including Fibrosis-4 (0.86) and the AST/alanine aminotransferase ratio (0.81) performed similarly well. The negative predictive value for ARLC was generally high (∼99.6%) across biomarkers, using routine clinical cutoffs to identify pathological values. However, positive predictive values were generally low (0.6%-15.9%).

CONCLUSIONS

Biomarkers commonly used in primary care settings are highly associated with incident ARLC in the general population. Elevation of these commonly available biomarkers should prompt consideration of further investigation of a possible high level of alcohol consumption.

A Population-Based Multigenerational Family Coaggregation Study of Severe Infections and Obsessive-Compulsive Disorder

BACKGROUND

Postinfectious autoimmune processes have been proposed as potential causal risk factors for obsessive-compulsive disorder (OCD). In this large population-based study, we aimed to clarify the familial coaggregation pattern between severe infections and OCD across clusters of relatives with varying degrees of relatedness.

METHODS

We identified 4,916,898 individuals born in Sweden between 1960 and 2008 and followed them until the end of 2020. Each individual was linked to their first-, second-, and third-degree relatives, including monozygotic and dizygotic twins, mothers, fathers, full siblings, maternal and paternal half siblings, aunts, uncles, and cousins. OCD and infection diagnoses from inpatient and specialized outpatient settings were retrieved from the Swedish National Patient Register. We compared the risk of OCD in relatives of probands with severe infections to those of probands without severe infections. Cox proportional hazard regression models, incorporating time-varying exposures, were used to estimate hazard ratios. Dose-response associations were examined using logistic regression models.

RESULTS

Relatives of probands with severe infections had a higher risk of OCD, which increased with genetic relatedness, with hazard ratios (95% CI) ranging from 1.46 (1.07-1.98) in monozygotic twins to 1.10 (1.09-1.11) in cousins. The results remained robust after adjusting for severe infections among relatives, OCD in probands, and comorbid autoimmune disorders in both probands and relatives. A dose-response association was observed between the number of infections in the probands and their odds of OCD, as well as in their relatives.

CONCLUSIONS

The results strongly suggest that the association between severe infections and OCD may be largely driven by shared genetic factors.

Outcomes After Thrombectomy for Primary and Secondary Medium Vessel MCA Occlusions: a Nationwide Registry Study

BACKGROUND

Medium vessel occlusions (MeVO) can be either isolated events (primary), or secondary to thrombus migration from a large vessel occlusion to a medium-sized vessel. Outcomes following endovascular thrombectomy (EVT) in the middle cerebral artery (MCA) may differ between primary and secondary MeVOs. This study aimed to assess the association between primary/secondary MeVOs and clinical outcomes following EVT in a nationwide patient cohort.

METHOD

Patients undergoing EVT were included in two Swedish quality registries. Secondary MeVO was defined as distal migration of a solitary thrombus between baseline CT-angiography and EVT, or basal ganglia infarction on postoperative CT in a patient that presented with a single MeVO on baseline CT-angiography. The primary outcome was good 90-day functional outcome (modified Rankin Scale 0-2). Postoperative change in the National Institutes of Health Stroke Scale-score (NIHSS), was a secondary outcome. Successfully revascularized patients (mTICI 2b-3) were compared with non-revascularized patients in exploratory analyzes.

RESULTS

Of the 5662 EVTs performed in Sweden (2018-2022), 1118 (20%) targeted solitary MCA territory MeVOs, with 819 (73%) being primary and 299 (27%) secondary. Functional outcomes did not differ between the primary and secondary MeVO groups (OR 0.86, CI 95% 0.65-1.14). Likewise, there was no significant difference in postoperative NIHSS scores (0.26, CI 95% -0.71 to 1.24), between groups (p = 0.597). Successful revascularization was associated with increased chance of good functional outcome for both primary (OR 3.77, CI95% 2.28-6.24, p < 0.001) and secondary MeVOs (OR 2.49, CI95% 1.21-5.14, p = 0.013).

CONCLUSIONS

Patients with a single primary or secondary MCA MeVOs have similar EVT outcomes and both groups seem to benefit from recanalization in exploratory analyses. This indicates that that EVT should not be withheld based on primary/secondary MeVO status.

Long-term risk for incident cancer in patients undergoing coronary artery bypass grafting with or without cardiopulmonary bypass: a nationwide population-based study

OBJECTIVES

It has been suggested that long-term risk for incident cancer is increased in patients operated with cardiopulmonary bypass. We compared the risk for incident cancer and cancer-specific death between patients undergoing coronary artery bypass grafting (CABG) with and without cardiopulmonary bypass.

METHODS

All patients without a history of cancer undergoing first-time CABG in Sweden during 1997-2020 were included in a nationwide population-based observational cohort study. Individual patient data from the SWEDEHEART registry and 4 other mandatory national registries were merged. The incidence of new cancer was compared between patients operated with or without cardiopulmonary bypass using multivariable Cox proportional hazards regression models adjusted for baseline characteristics, co-morbidities, socioeconomic factors and time of surgery. A propensity score-matched analysis with 3735 well-balanced pairs was also performed.

RESULTS

A total of 81 097 patients undergoing CABG with (n = 77 345) and without cardiopulmonary bypass (n = 3752) were included. Median follow-up was 8.2 (interquartile range 4.0-13.2) years. The crude event rates were 2.71 and 2.68 per 100 person-years in the patients operated with and without cardiopulmonary bypass, respectively. There was no difference in the adjusted risk for cancer between the groups [adjusted hazard ratio 0.95 (95% confidence interval; CI 0.90-1.01)] or in the risk for cancer-specific death between the groups [adjusted hazard ratio 0.99 (95% CI 0.89-1.09)]. The propensity score-matched analysis showed similar results [hazard ratio 0.96 (95% CI 0.89-1.04) and 0.99 (95% CI 0.85-1.13)], respectively.

CONCLUSIONS

Cardiopulmonary bypass is not associated with an increased risk of incident cancer or cancer-specific mortality in patients undergoing CABG.

Implications of pacemaker implantation after aortic valve surgery for endocarditis: a nationwide study†

OBJECTIVES

Infective endocarditis (IE) is associated with a high risk of atrioventricular block and surgery adds to the risk of receiving a permanent pacemaker. The clinical impact of pacemaker implantation in IE patients is insufficiently studied. Our objective was to analyse long-term clinical outcomes in patients who receive a permanent pacemaker after IE surgery.

METHODS

We conducted a nationwide observational cohort study, including all patients undergoing surgery for aortic valve IE in Sweden 1997-2022. The exposure group was patients who received a permanent pacemaker within 30 days of surgery. We used inverse probability of treatment weighting to account for inter-group differences and flexible parametric models to estimate hazards and cumulative incidences. Outcomes were all-cause mortality, heart failure and reinfection in the prosthetic valve.

RESULTS

Among 2175 patients who underwent surgery for aortic valve endocarditis, 168 (8%) received a permanent pacemaker. The mean age was 59 years; 18% were female. During a mean follow-up of 8.0 years (maximum 26 years), 822 patients (38%) died. At 15 years, the cumulative incidence of all-cause mortality was 60% versus 50% in the pacemaker versus the no pacemaker group; for heart failure, it was 21% versus 16%. We found no association of pacemaker implantation with mortality [hazard ratio (HR) 1.17; 95% confidence interval (CI) 0.86-1.58], heart failure (HR 1.42; 95% CI 0.89-2.29) or reinfection (HR 0.85; 95% CI 0.50-1.45).

CONCLUSIONS

Pacemaker implantation after surgery for aortic valve IE is common but was not associated with an increased risk of death, heart failure or reinfection. Although pacemaker need suggests more advanced disease, these results show that lifesaving surgery is not importantly jeopardised by the need for a pacemaker.

Sociodemographic and clinical characteristics of 1,234 individuals diagnosed with trichotillomania in the Swedish National Patient Register

Trichotillomania is an understudied, underrecognized, and difficult-to-treat psychiatric disorder that affects about 1-2% of the population, predominantly women. This study aimed to characterize the sociodemographic and clinical characteristics of a Swedish cohort of individuals with a diagnosis of trichotillomania assigned in specialist services across the country. Through the Swedish National Patient Register, we identified all individuals with an ICD-10 diagnosis of trichotillomania between January 1st, 1997 and December 31st, 2020. The cohort included 1,234 individuals, with a median age at first diagnosis of 25 years (interquartile range, 16-35). Most individuals were female (85%) and single (82%). Most (79%) individuals had a comorbid psychiatric disorder diagnosed during the study period. Anxiety-related disorders (65%), depressive disorders (48%), and neurodevelopmental disorders (39%) were the most frequent co-occurring diagnoses. Most (72%) individuals were dispensed psychotropic medications during the period ranging from 12 months prior to and 12 months after the first trichotillomania diagnosis. Antidepressants (58%), hypnotics/sedatives (36%), and anxiolytics (31%) were the most frequently dispensed medications. Altogether, the characteristics of individuals diagnosed with trichotillomania in Swedish specialist services were similar to those reported in previous literature, opening the possibility of register-based research into this underdiagnosed and understudied condition.

Prevalence and predictors of healthcare use for psychiatric disorders at 9 years after a first episode of psychosis: a Swedish national cohort study

BACKGROUND

Psychotic disorders are known to exhibit heterogeneity with regards to illness course and prognosis, yet few studies have examined long-term healthcare use.

OBJECTIVE

To determine the prevalence and predictors of healthcare use for psychiatric disorders at 9 years after the first episode of psychosis (FEP).

METHODS

National registers were used to identify all Swedish residents aged 18-35 years with FEP between 2006 and 2013. The 12-month period-prevalence of secondary healthcare use was determined at each year of the 9-year follow-up, categorised according to main diagnosis (psychotic disorder vs other psychiatric disorder vs none vs censored). Multinomial logistic regression models were used to examine associations between baseline characteristics and healthcare use at 9 years and derive predicted probabilities and 95% CIs for the four outcome groups, for each predictor variable.

FINDINGS

Among 7733 individuals with FEP, 31.7% were treated in secondary healthcare for psychotic disorders at the 9-year follow-up, 24.1% were treated for other psychiatric disorders, 35.7% did not use healthcare services for psychiatric disorders and 8.5% were censored due to death/emigration. Having an initial diagnosis of schizophrenia was associated with the highest probability of secondary healthcare use for psychotic disorder at 9 years (0.50, 95% CI (0.46 to 0.54)] followed by inpatient treatment at first diagnosis (0.37, 95% CI (0.35 to 0.38)).

CONCLUSION

Although 56% of individuals with FEP were treated for psychiatric disorders in secondary healthcare 9 years later, a substantial proportion were treated for non-psychotic disorders.

CLINICAL IMPLICATIONS

Individuals with an initial diagnosis of schizophrenia, who received their first diagnosis in inpatient settings, may need more intensive treatment to facilitate remission and recovery.

The application of population data linkage to capture sibling health outcomes among children and young adults with neurodevelopmental conditions. A scoping review

Introduction

Siblings of children with neurodevelopmental conditions have unique experiences and challenges related to their sibling role. Some develop mental health concerns as measured by self-reported surveys or parent report. Few data are available at the population level, owing to difficulties capturing wide-scale health data for siblings. Data linkage is a technique that can facilitate such research.

Objective

To explore the application of population data linkage as a research method to capture health outcomes of siblings of children with neurodevelopmental conditions.

Inclusion criteria

Peer reviewed papers that captured health outcomes for siblings of children and young adults with neurodevelopmental conditions using population data linkage.

Methods

JBI Scoping review methods were followed. Papers were searched within CINAHL, Ovid, Scopus, and Web of Science from 2000 to 2024 using search terms relating to 'data linkage' 'neurodevelopmental conditions' 'siblings' and 'health outcomes'.

Results

The final data extraction included 31 papers. The neurodevelopmental conditions of index children were autism, attention deficit hyperactivity disorder, intellectual disability, cerebral palsy and developmental delay. The mean follow-up time was 31 years, and the majority of studies originated from Scandinavia. Sibling health outcomes observed were psychiatric diagnoses, self-harm and suicide, other neurodevelopmental conditions, and medical conditions such as atopic disease, cancer and obesity.

Conclusion

Data linkage can help capture sibling health outcomes quickly across large cohorts with a range of neurodevelopmental conditions. Future research could be enhanced by focusing on siblings as the primary group of interest, increased integration of genealogical data, and comparisons between diagnostic groups and severity levels. Adoption of established rigorous reporting methods will increase the replicability of this type of research, and provide a stronger evidence-base from which to inform sibling supports.

Lack of association between breastfeeding duration and body mass index in children and adolescents - A Swedish cohort study

AIMS

The aim of the study was to investigate the association between breastfeeding duration and body mass index (BMI), overweight and obesity in children during follow-up until 16 years of age.

METHODS

Observational cohort study of mothers and their children born 1999-2000 in a municipality in southwestern Sweden. Data were retrieved from antenatal clinics, primary care child health care centres and school health care. The study exposure was breastfeeding duration measured in months and categorised by duration < 6 months and ≥ 6 months. The study outcomes were development of BMI, and overweight and obesity according to ISO-BMI.

RESULTS

The study population comprised 312 mothers and their 319 children of whom 120 were breastfed < 6 months and 199 ≥ 6 months. The overall partial or exclusive median breastfeeding duration was 6.5 months. No associations were found between breastfeeding duration in months and BMI in unadjusted (p = 0.70) and adjusted (p = 0.92) linear mixed-effects models with repeated BMI recordings at approximately 4, 7, 10, 13 and 16 years. Further, no associations were found in subgroup analyses for girls and boys. The adjusted analyses were adjusted for maternal age, smoking, BMI and parity, and for the child's sex, gestational age at birth and birth weight. Unadjusted logistic mixed-effects models with repeated ISO-BMI classifications at approximately 4, 7, 10, 13 and 16 years showed no associations between breastfeeding duration (≥6 months versus < 6 months) and overweight or obesity as compared to underweight or normal weight, in total (odds ratio 1.46, 95% confidence interval 0.69-3.08) or in boys and girls separately.

CONCLUSIONS

We found no association between breastfeeding duration and childhood and adolescence BMI up to 16 years of age or the development of overweight or obesity.

Cholecystectomy is a Risk Factor for Microscopic Colitis: A Nationwide Population-based Matched Case Control Study

BACKGROUND & AIMS

Studies have linked bile acid malabsorption and microscopic colitis (MC), with some patients with MC responding to treatment with bile acid sequestrants. However, the literature on cholecystectomy as a risk factor for MC is inconclusive. Therefore, we investigated the relationship between cholecystectomy and MC on a nationwide scale to provide more definitive insights.

METHODS

We conducted a nationwide matched case-control study involving 13,554 patients diagnosed with MC between 1981 and 2017 in Sweden who were matched to 64,886 controls. Data on MC were obtained from Swedish pathology registers, and controls were randomly selected from the general population and matched according to birth year, sex, county of residence, and calendar year. Moreover, MC-free full siblings to patients with MC were identified. Information on cholecystectomy was collected from the Swedish National Patient Register. Adjusted odds ratios (aORs) were calculated using multivariable-adjusted conditional logistic regression.

RESULTS

The median age at diagnosis was 63.5 years (interquartile range [IQR], 51.0-73.4 years), and 72.3% of MC patients were women. Among patients with MC, 342 (2.5%) had undergone a cholecystectomy before diagnosis, compared with 687 (1.1%) in the control group. This yielded an aOR of 2.36 (95% confidence interval [CI], 2.07-2.69) for earlier cholecystectomy in patients with MC. The corresponding aORs for collagenous colitis and lymphocytic colitis were 1.87 (95% CI, 1.48-2.36) and 2.65 (95% CI, 2.26-3.12), respectively. When compared with siblings, the aOR was 1.49 (95% CI, 1.21-1.85).

CONCLUSIONS

Cholecystectomy is associated with an increased risk of subsequent MC. These findings have implications for surgeons and general practitioners and underscore the need for further research into the underlying association between bile acid and MC.

Income and work loss in patients with Addison's disease: a nationwide population-based study

OBJECTIVE

Autoimmune Addison's disease (AAD) is associated with reduced health-related quality of life and possibly reduced employability. The aim of this study was to assess differences in income and work loss between patients with AAD and matched comparators.

DESIGN

Nationwide, cross-sectional register-based study.

METHODS

By linking the Swedish Addison Register and national health registers, we identified working age (18-64 years) individuals with AAD and general population comparators (matched 1:5 by sex, age, and county of residence). We assessed differences in taxable earnings and disposable income through quantile regression and differences in work loss through linear regression during 2019.

RESULTS

We identified 1140 cases with AAD and 5700 comparators (mean age 46.1 years, 48.4% men). Type 1 diabetes was prevalent in 15.7% and 1.1%, respectively. Work loss was higher in AAD; adjusted mean difference 14.4 days; 95% CI, 8.6-20. The adjusted median differences in taxable earnings and disposable income were non-significant overall at -617 (95% CI; -2317 to 1083) and -405 (95% CI; -1417 to 607) €. However, significantly lower taxable earnings and disposable income were found among patients with short education: -5303 (95% CI; -9603 to -992) and -3754 (95% CI; -6486 to -1022) €, or concomitant type 1 diabetes: -5808 (95% CI; -9937 to -1690) and -3349 (95% CI; -6203 to -506) €.

CONCLUSION

Patients with AAD had more work loss, yet overall similar taxable earnings and disposable incomes versus comparators. Patients with AAD with shorter education or type 1 diabetes were most socioeconomically vulnerable.

Sickness absence and disability pension in patients treated with mechanical thrombectomy

BACKGROUND

Stroke patients with large vessel occlusions risk long-term or permanent sickness absence. We aimed to analyze the proportions and days of sickness absence and disability pension in thrombectomy-treated patients.

METHODS

A register-based nationwide longitudinal cohort study of stroke patients treated with mechanical thrombectomy in 2016-2021 in Sweden (identified through the Swedish Board of Health and Welfare procedural code for care interventions, KVÅ:AAL15). All thrombectomy-treated patients aged 18-63 were followed one year prior and one after stroke. Proportions (%) and number of net days of sickness absence and disability pension were calculated. Predictors for absence were calculated through multinomial regression analysis.

RESULTS

We included 672 patients, mean age was 53 years and 66 % were men. The proportion of patients on sickness absence decreased from 70.4 % at 30 days to 63.2 % at 90 days after stroke onset. Proportions of sickness absence and disability pension did not differ between women and men after treatment. Amongst predictors for having full-time absence at 90 days were: OR (95 % CI) being born in Europe (excl. Nordic countries) 2.17 (1.15-4.11), being single 1.59 (1.12-2.26), elementary education 2.08 (1.21-3.57), and living in a town or suburb 1.47 (1.01-2.14). Patients with no income 0.21 (0.13-0.35) or the lowest income level 0.36 (0.22-0.58) had low odds for full-time sickness absence and disability pension at 90 days.

CONCLUSIONS

One third of thrombectomy-treated patients had no sickness absence nor disability pension at day 30 after stroke, and the proportion of patients without absence increased during follow-up. Absence proportions and predictors for full-time absence were centered around income level, educational level, birth country, and type of living area. Notably, there were no sex differences.

Early Creatinine Changes After Aortic Valve Replacement and Late Survival, Heart Failure, and Chronic Kidney Disease in a National Registry

BACKGROUND

The impact of small increases in serum creatinine after surgical aortic valve replacement (SAVR) that fail to meet the acute kidney injury stage 1 criteria is unknown. The aim of this study was to investigate prognosis after primary SAVR in patients with small increases in postoperative serum creatinine.

METHODS

This observational cohort study included all adult patients who underwent primary SAVR in Sweden from 2009 to 2022. The primary outcome was all-cause mortality. Secondary outcomes were chronic kidney disease and heart failure. Regression standardization addressed confounding.

RESULTS

In 16,766 patients, 4074 (24.2%) had no change in postoperative serum creatinine, 5764 (34.3%) had a small increase in postoperative serum creatinine (0.06 mg/dL ≤ Δserum creatinine <0.3 mg/dL), and 2753 (16.4%) fulfilled the Kidney Disease Improving Global Outcomes acute kidney injury stage 1 criteria. The mean age was 67 years, and 31% of patients were female. No significant difference in long-term all-cause mortality was observed in the no change group at 13 years compared with the small increase group (absolute survival difference, 2.3% [95% CI, 0%-4.6%]). A stepwise increase in the risk of 30-day mortality was observed with increasing changes in serum creatinine. At 13 years of follow-up, there was a significant difference in the risk of chronic kidney disease (absolute difference, 2.8% [95% CI, 1.0%-4.5%]) and heart failure (absolute difference, 3.5% [95% CI, 1.3%-5.7%]) between the no change and small increase groups.

CONCLUSIONS

A small increase in postoperative serum creatinine after SAVR was associated with an increased risk of adverse outcomes. The acute kidney injury definition may benefit from including more reliable and specific biomarkers together with small creatinine increases to detect kidney injury.

Long-term risk of HCC in a DAA-treated national hepatitis C cohort, and a proposed risk score

BACKGROUND

The risk of hepatocellular carcinoma (HCC) remains elevated in cirrhotic hepatitis C patients with sustained virological response (SVR) after DAA treatment. We assessed long-term HCC risk stratified by pretreatment liver stiffness measurement (LSM) and developed a risk score algorithm.

METHODS

This register-based nationwide cohort study of 7,227 DAA-treated patients with SVR evaluated annual HCC incidence rates (IRs) and cumulative incidences stratified by pretreatment LSM. The association between LSM and HCC risk was analyzed using multivariate Cox regression. A risk score algorithm was developed and internally validated in 2,664 individuals with LSM >9.5 kPa, assigning each patient a score based on risk factors, proportionally weighted by the association with HCC risk.

RESULTS

During a median follow-up of 1.8 years (3.2 years for LSM ≥12.5 kPa), 92 patients (1.3%) developed HCC. The IRs for LSM 9.5-12.4, 12.5-19.9 and ≥20 kPa were 0.21, 0.99 and 2.20 HCC/100 PY, respectively, with no significant risk reduction during follow-up. The HRs (and 95% CI) for LSM 9.5-12.5, 12.5-19.9 and ≥20 kPa are 1.19 (0.43-3.28), 4.66 (2.17-10.01) and 10.53 (5.26-21.08), respectively. Risk score models including FIB-4, alcohol, diabetes, age and LSM effectively stratified patients with LSM >9.5 kPa into low-, intermediate- and high-risk groups, with a Harrell's C of 0.799. Notably, 48% with LSM ≥9.5 kPa and 27% ≥12.5 kPa were classified as low-risk.

CONCLUSION

Pretreatment LSM is associated with HCC risk, which remains stable during the initial five years post-SVR. The HCC risk score algorithm effectively identifies low-risk patients, who may not require HCC surveillance.

Effect of Pediatric Obesity Treatment on Long-Term Health

IMPORTANCE

Data regarding the long-term impact of treating childhood obesity on the risk of obesity-related events, including premature mortality, are limited.

OBJECTIVE

To evaluate the long-term effect of different responses to pediatric obesity treatment on critical health outcomes in young adulthood.

Design, Setting, and Participants

The study included a dynamic prospective cohort of children and adolescents with obesity within The Swedish Childhood Obesity Treatment Register (BORIS) and general population comparators, linked with national registers. Baseline data were collected between 1996 and 2019. Formal analyses for this study was conducted in 2023. Outcomes were assessed from individuals aged 18 to 30 years (2005 to 2020). Participants included children and adolescents aged 6 to 17 years receiving at least 1 year of obesity treatment. General population comparators were matched on a ratio of 1:5 on sex, year of birth, and geographical area.

EXPOSURE

Pediatric obesity treatment response was based on changes in body mass index standard deviation score and categorized as poor, intermediate, and good response and obesity remission.

MAIN OUTCOMES

Obesity-related events included type 2 diabetes (T2D), dyslipidemia, hypertension, depression or anxiety, and weight-loss bariatric surgery. Additionally, mortality was assessed.

RESULTS

Of 6713 individuals (3777 male [56%] and 2936 female [44%]), the median age at obesity treatment initiation was 12.1 (quartile 1; quartile 3: 10.1; 14.3) years and treatment duration was 3.0 (1.8; 4.9) years. For T2D, hypertension, dyslipidemia, weight-loss bariatric surgery, and depression or anxiety outcomes, unadjusted incidence rates tended to decrease with better treatment response and the lowest estimate was observed among general population comparators. Compared with poor response, obesity remission or a good response in obesity treatment was associated with reduced risk of mortality (adjusted hazard ratio [HR], 0.12; 95% CI, 0.03-0.46). Good response was also associated with lower risk of TD2 (HR, 0.42; 95% CI, 0.23-0.77), dyslipidemia (HR, 0.31; 95% CI, 0.13-0.75), and bariatric surgery (HR, 0.42; 95% CI, 0.30-0.58). Obesity remission showed similar reduced risk, but also a reduced risk of hypertension (HR, 0.40; 95% CI, 0.24-0.65). Treatment response was not associated with depression or anxiety.

CONCLUSIONS AND RELEVANCE

In this study, beneficial pediatric obesity treatment response yielded enduring health benefits, markedly lowering future morbidity and mortality risks in young adulthood.

Sickness absence and disability pension patterns before and after ischemic stroke: A Swedish longitudinal cohort study with matched references

INTRODUCTION

The aim was to determine ischemic stroke patients' sickness absence and disability pension before and after stroke, and compare these to that of matched references.

PATIENTS AND METHODS

All working-aged individuals (aged 18-61) in Sweden with incident ischemic stroke in year 2000, 2005, 2010, or 2015, respectively, and five population-based matched references to each stroke patient. Each cohort was followed 1 year prior stroke and 3 years after. We calculated rates and mean days of sickness absence and disability pension among stroke patients and references and computed trajectories of absence days with predictors of high sickness absence and disability pension.

RESULTS

Number of patients with incident ischemic stroke in 2000 (N = 2728), 2005 (N = 2738), 2010 (N = 2767), and 2015 (N = 2531). Mean stroke age was 53 years and rate of men was 64%. Mortality rate within 12 months after stroke date decreased from 8.1% in 2000 to 4.8% in 2015. Sickness absence for patients was 31.1% in the year prior their stroke, versus 13.7% for references, both groups mainly due to mental and musculoskeletal diagnoses. Factors associated with future high mean number of sickness absence and disability pension days were elementary educational level; adjusted OR (CI) 3.47(2.38-5.05), being single; 1.67(1.29-2.16), female sex 1.72(1.31-2.26), diabetes; 1.86(1.18-2.92), and aged >50; 2.25(1.69-2.98).

DISCUSSION AND CONCLUSION

Ischemic stroke patients have more absence days compared to matched references even before the stroke, mainly related to mental and musculoskeletal diagnoses. Future research should address the impact of efficient stroke treatment on sickness absence and disability pension.

Midwifery Continuity of Care During Pregnancy, Birth, and the Postpartum Period: A Matched Cohort Study

OBJECTIVE

To compare pregnancy outcomes in a midwifery continuity of care (MCoC) model to standard midwifery care in Sweden.

DESIGN

Matched cohort study.

SETTING

Public healthcare during pregnancy and childbirth, Stockholm, Sweden.

POPULATION

Women giving birth at Karolinska University Hospital site Huddinge in Stockholm between January 1, 2019, and August 31, 2021.

METHODS

Data on all births including MCoC and standard care, during the time period, were retrieved from the national Swedish Pregnancy Register. Propensity score matching was applied to obtain a matched set from the standard care group for every woman in the MCoC model. Based on the matched cohort, we estimated risk ratios (RR) for binary outcomes with 95% confidence intervals (CI).

MAIN OUTCOME MEASURES

Interventions during labor, mode of birth, and preterm birth (< 37 gestational weeks).

RESULTS

Compared with standard care, women in the MCoC model were more likely to give birth spontaneously (RR 1.06 95% CI 1.02-1.10) and less likely to have an elective cesarean on maternal request (RR 0.24 95% CI 0.11-0.51). The risk of preterm birth was also reduced in the MCoC group (RR 0.51 95% CI 0.32-0.82).

CONCLUSION

The MCoC model was associated with fewer medical interventions and improved pregnancy outcomes.

Myocardial infarction in second-generation immigrants compared to native-born Swedes in the total population of Sweden

BACKGROUND AND AIMS

Environmental and genetic factors predispose to cardiovascular disease. Some first-generation immigrants have a higher cardiovascular risk in Sweden, while less is known about second-generation immigrants. We aimed to analyze the risk of acute myocardial infarction (AMI) among second-generation immigrants in Sweden.

METHODS

We included all individuals 18 years of age and older in Sweden, n = 4,580,967. AMI was defined as at least one registered diagnosis in the National Patient Register between January 1, 1998, and December 31, 2018. Cox regression analysis was used to estimate the relative risk (hazard ratio = HR) with 99 % confidence interval (CI) of incident AMI with adjustments made for age, sociodemographics, and comorbidities, and also subdivided into two age groups, i.e., 18-54 years and ≥55 years.

RESULTS

A total of 158,815 AMI events were registered. Fully adjusted models showed HRs (99 % CI) in second-generation immigrants for men 1.05 (1.01-1.08), and for women 0.99 (0.94-1.05). A marginally higher MI risk was found only among men with parents from the Nordic countries in the fully adjusted model, HR 1.05 (1.01-1.10), and a lower risk only among women with parents from Asian countries, HR 0.47 (0.30-0.75). No significant overall differences in AMI risk were seen in older and younger second-generation immigrants.

CONCLUSIONS

The overall risk of AMI was similar for most groups of men and women with foreign-born parents compared to native-born Swedes. Our findings suggest that environmental factors may be more important than genetic factors, but further studies are needed to quantify these risks concerning AMI.

Impact of an intervention for osteoarthritis based on exercise and education on metabolic health: a register-based study using the SOAD cohort

OBJECTIVE

This study evaluated the effects of a 6-week osteoarthritis (OA) exercise and education intervention on metabolic health markers, including blood pressure (BP), glycated haemoglobin (HbA1c), high-density lipoprotein (HDL), cholesterol levels and weight in individuals with both OA and diabetes.

METHODS

Data originated from the Swedish Osteoarthritis and Diabetes cohort, which is composed of the Swedish Osteoarthritis Register (SOAR) and National Diabetes Register. We included individuals diagnosed with OA and diabetes who underwent the intervention between January 2008 and December 2019, matched with controls with diabetes who did not based on birth year, sex, OA site (hip/knee) and OA diagnosis year. Outcomes included BP, HbA1c, HDL, total cholesterol levels and weight measured up to 3 years before and after SOAR enrolment. Statistical analyses used two-way fixed-effect models.

RESULTS

The study included 4571 individuals with OA and diabetes (mean age: 69.5, SD: 7.8; women: 52.7%; knee OA: 71.2%) and 7925 controls. The intervention group showed a systolic BP decrease of approximately 1.0 mm Hg at 6 and 12 months compared with the control group. HDL levels increased by about 0.02 mmol/L at 12, 18 and 24 months. Weight decreased by approximately 0.5 kg at 6, 18 and 30 months. HbA1c levels increased by approximately 0.5 mmol/mol at 6 months. No essential differences were found in the total cholesterol levels.

CONCLUSION

An OA exercise and education intervention designed following OA clinical practice guidelines led to small and unlikely clinically relevant improvements in metabolic health markers in individuals with OA and diabetes.

Adverse pregnancy outcomes, familial predisposition, and cardiovascular risk: a Swedish nationwide study

BACKGROUND AND AIMS

Adverse pregnancy outcomes (APOs) are recognized as significant female-specific risk factors for cardiovascular disease (CVD). A potential shared familial susceptibility between APOs and CVD has been proposed, but not thoroughly explored. This study employs a quasi-experimental family comparison design to investigate shared familial predisposition between APOs and CVD, by assessing risk of CVD in APO-exposed women and their APO-free sisters.

METHODS

Nationwide population-based cohort study encompassing primiparous women, without prior CVD, with registered singleton births in the Swedish Medical Birth Register between 1992 and 2019, grouped into: women with ≥1 APO (165 628), APO-free sisters (60 769), and unrelated APO-free comparator women (992 108). All study participants were followed longitudinally, through linkage with national health registers, from delivery until 2021, for primary endpoint major adverse cardiac events, and its individual components: ischaemic heart disease, heart failure, and cerebrovascular events.

RESULTS

Over a median follow-up of 14 years, APO-exposed women exhibited increased rates of CVDs compared with APO-free comparators. Adverse pregnancy outcome-free sisters exhibited elevated adjusted hazard ratios (aHRs) of major adverse cardiac event {aHR 1.39 [95% confidence interval (CI) 1.13-1.71]}, heart failure [aHR 1.65 (95% CI 1.14-2.39)], and cerebrovascular events [aHR 1.37 (1.04-1.72)] compared with the APO-free comparators, while no significant increase in ischaemic heart disease was observed. Within-family analysis revealed lower CVD rates in APO-free sisters compared with their APO-exposed counterparts, except for no significant difference in cerebrovascular events.

CONCLUSIONS

Sisters of women with APOs face a moderately increased risk of CVD, suggesting a genetic and/or environmental influence on the association between APOs and CVDs. These findings underscore the need for evaluating the effectiveness of targeted preventive measures in women with APOs and their sisters.

Long-term outcomes after neonatal acidemia

BACKGROUND

Sustained intrauterine hypoxia causes some 1 million perinatal deaths annually worldwide. The condition is predicated by neonatal acidemia, as determined by pH in the umbilical cord blood at birth. We aimed to evaluate the association between umbilical cord arterial pH and long-term outcomes up to 20 years of follow-up.

STUDY DESIGN

Using a retrospective cohort design, the umbilical cord arterial pH values from singleton births at Skåne University Hospital Malmö, Sweden, from 1997 to 2012 were cross-linked to data from the Swedish Medical Birth Register, Swedish Patient Register, and Cause of Death Register. The hazard ratio for developing disease later in life, as defined organ-wise with the International Classification of Diseases version 10 with codes 00 to 99, was calculated relative to umbilical cord arterial pH <7.05 and ≥7.05, respectively. In addition, umbilical cord arterial pH thresholds at 6.95, 7.00, 7.05, 7.10, 7.15, and 7.20 were evaluated for mental and behavioral disorders.

RESULTS

Of the 35,931 births that met the inclusion criteria of complete and validated data, 912 (2.5%) had acidemia (umbilical cord arterial pH <7.05) at birth, while 35,019 (97.5%) had nonacidemic values (pH ≥7.05). Acidemia was associated with higher mortality (P=.043). Among groups of organ system diseases, a pH <7.05 was not associated with increased risk of disease. At the group level, the risk was not significantly increased for mental and behavioral disorders (crude hazard ratio 1.05, 95% confidence interval 0.75-1.46); however, subanalysis showed an increased risk of cerebral palsy (crude hazard ratio 4.30, 95% confidence interval 2.16-8.58) and epilepsy (crude hazard ratio 1.70, 95% confidence interval 1.02-2.86). After adjustment for maternal age, parity, smoking, body mass index, and gestational age, the associations strengthened (cerebral palsy adjusted hazard ratio 4.35, 95% confidence interval 2.17-8.73), (epilepsy adjusted hazard ratio 1.71, 95% confidence interval 1.02-2.88). The threshold of umbilical cord arterial pH <6.95 was significantly associated with increased risk of cerebral palsy (hazard ratio 18.38, 95% confidence interval 7.34-46.08), epilepsy (hazard ratio 8.16, 95% confidence interval 4.18-15.92), and intellectual disability (hazard ratio 4.19, 95% confidence interval 1.73-10.17), whereas thresholds 7.00, 7.05, 7.10, and 7.15 were not.

CONCLUSION

Neonatal acidemia, defined as cord arterial pH <7.05, was associated with an increased risk of death, cerebral palsy, and epilepsy, but not of other types of mental and behavioral disorders or other organ system diseases. An umbilical cord arterial pH <6.95 was significantly associated with cerebral palsy, epilepsy, and intellectual disability whereas pH <7.00 and other thresholds between 7.05 and 7.20 were not.

Comorbidities, Endocrine Medications, and Mortality in Prader-Willi Syndrome-A Swedish Register Study

Background: Prader-Willi Syndrome (PWS) is a rare, genetic, multi-systemic disorder. Its main characteristics are muscular hypotonia, behavioral problems, intellectual disability, endocrine deficiencies, hyperphagia, and a high risk of morbid obesity and related comorbidities. This study aimed to investigate the rate of comorbidity, prescription of endocrine medications, and mortality in individuals with PWS compared to the general population. Methods: The association between PWS and outcomes were investigated in a matched cohort study of individuals born in the period of 1930-2018 with data from Swedish national health and welfare registers. Each individual was matched with 50 non-PWS comparisons. The associations between PWS, outcomes and prescribed endocrine medications were estimated through Cox proportional hazard models, presented as Hazard Ratios (HR) with 95% Confidence Intervals (CIs). Results: Among 360 individuals (53% men) with PWS, 16% had diabetes mellitus, 6% heart failure, 4% vein thrombosis, 2% atrial fibrillation, 2% coronary heart disease, and 1% pulmonary embolism. Individuals with PWS had an increased rate of heart failure (HR: 23.85; 95% CI: 14.09-40.38), diabetes mellitus (HR: 17.49; 95% CI: 12.87-23.74), vein thrombosis (HR: 10.44; 95% CI: 5.69-19.13), pulmonary embolism (HR: 5.77; 95% CI: 2.27-14.67), atrial fibrillation (HR: 5.19; 95% CI: 2.48-10.86), and coronary heart disease (HR: 3.46; 95% CI: 1.50-7.97) compared to non-PWS individuals. Somatotropin was prescribed in 63%, antidiabetics in 18%, and thyroid hormones in 16% of the PWS individuals (<1%, 2%, and 3%, respectively, in non-PWS individuals). The rate of mortality was fifteen times higher in PWS than in non-PWS, with a mean age at death of 42 years. Conclusions: The rates of diabetes mellitus and cardiovascular comorbidities were higher in individuals with PWS. As expected, the prescription of somatotropin was high, but the endocrine prescription pattern also reflected the high prevalence of diabetes mellitus and thyroid illness. Although the mean age at death was older than previously reported, a higher awareness and intensified efforts to avoid obesity, as well as the prevention and early treatment of cardiovascular and endocrine comorbidity, are crucial aims in the care of people with PWS.

Relapse in substance-induced psychosis and associated risk factors. A Nationwide register-linkage study from Sweden

BACKGROUND AND AIMS

Substance-induced psychoses (SIP) have the potential to relapse and convert into schizophrenia-spectrum disorders. However, risk factors associated with SIP relapse remain unknown. The aim of this study was to measure the incidence and risk of SIP relapse and associating risk factors.

DESIGN, SETTING AND PARTICIPANTS

Population based register study that identified people with first-time SIP between 2006 and 2016 (n = 7320) from Swedish nation-wide registers to examine incidence of relapse and associated risk factors during 2-year follow-up. Participants were censored to death, emigration and the diagnosis of other psychotic illness. Risk factors associated with relapse were studied using multivariable Cox models.

MEASUREMENTS

SIP was measured via related diagnostic codes (ICD-10: F1x.5) collected from the National Patient Register (NPR). SIP relapse was measured as hospitalization due to SIP during 2-year follow-up also collected from the NPR. Potential risk factors included demographic characteristics, psychiatric comorbidities, sickness absence and disability pension collected from nationwide registers.

FINDINGS

Of the study population (n = 7320), 20.0% (n = 1463) had a SIP relapse during the follow-up (median time 126 days, interquartile range 56-321) and 83.3% had the same type of SIP as their first SIP. Relapse was most common for those whose first SIP was induced by cannabis (25.7%), followed by multi-substance use (23.8%) and (meth)amphetamine (19.7%). Factors associated with SIP relapse were previous substance use disorder [hazard ratio (HR) = 1.37, 95% confidence interval (CI) = 1.20-1.56], younger age (16-29 years, HR = 1.29, 95% CI = 1.05-1.58, versus 50-65), being born abroad (HR = 1.23, 95% CI = 1.07-1.41), attention deficit hyperactivity disorder (HR = 1.21, 95% CI = 1.05-1.39), having had 1-90 days sick leave during the previous year (HR = 1.19, 95% CI = 1.01-1.44), and cannabis- (HR = 2.42, 95% CI = 1.98-2.96), (meth)amphetamine- (HR = 1.49, 95% CI = 1.23-1.81) or multi-substance- (HR = 1.81, 95% CI = 1.52-2.15) induced psychosis compared with alcohol-induced psychosis.

CONCLUSIONS

In Sweden, 20% of people with substance-induced psychosis between 2006 and 2016 had a relapse within 2 years follow-up. Cannabis-induced psychosis had the shortest time lapse between episodes. Risk factors for relapse included attention deficit hyperactivity disorder, substance-use disorder, younger age, previous sickness absence and being born outside Sweden.

Sickness absence among privately employed white-collar workers during the COVID-19 pandemic; a prospective cohort study

BACKGROUND

The COVID-19 pandemic brought with it several changes, both regarding infection with COVID-19 itself as well as measures to combat the spread of infection, that might have affected sickness absence (SA) patterns. The aim was to explore whether incidence and length of SA changed between 2019, 2020, and 2021, as well as to determine factors associated with SA due to COVID-19 or COVID-like diagnoses among privately employed white-collar workers.

METHODS

A cohort of all privately employed white-collar workers in 2018 in Sweden (n = 1 347 778; 47% women) was followed prospectively during 2019, 2020, and 2021 using linked nationwide register data. We calculated numbers and proportions of people with incident SA (in SA spells > 14 days) due to COVID-19, COVID-like diagnoses (certain respiratory, infectious, and symptom-based diagnoses used in the beginning of the pandemic for suspected COVID-19), and all other SA, respectively, and mean number of SA days with somatic and mental diagnoses. Logistic regression was used to determine odds ratios (OR) and 95% confidence intervals for associations between prior diagnosis-specific SA, sociodemographic and work-related factors and incident SA due to COVID-19 or COVID-like diagnoses.

RESULTS

In 2020, 0.6% of the women and 0.3% of the men had incident SA due to COVID-19. For SA with COVID-like diagnoses, the corresponding proportions were 1.2% and 0.5%. The proportion of people with all other SA was stable across the years, at 8.1-8.4% for women and 3.7-3.9% for men. The mean number of SA days per person increased each year for somatic diagnoses but for mental diagnoses it decreased from 2019 to 2020 and increased to 2021 among women and men. Factors associated most strongly with incident SA due to COVID-19 or COVID-like diagnoses were low income (adjusted OR-range 1.36-5.67 compared to the highest income group) and prior SA due to COVID-like diagnoses (OR-range 4.67-5.31 compared to those with no such prior SA).

CONCLUSIONS

A small proportion of privately-employed white-collar workers had incident SA spells > 14 days due to COVID-19 or COVID-like diagnoses. The factors associated with SA due to COVID-19 were similar to factors associated with SA due to other diagnoses in previous studies.

Childhood-onset inflammatory bowel disease and chronic non-bacterial osteomyelitis: a Swedish nationwide cohort study 2002-2022

BACKGROUND AND AIMS

Nationwide, population-based studies of chronic non-bacterial osteomyelitis (CNO) in patients with childhood-onset inflammatory bowel disease (IBD) are lacking.

METHODS

We used nationwide registers to identify all children in Sweden diagnosed with IBD during 2002-2022 and the occurrence of CNO in this IBD cohort and general population non-IBD comparators. To estimate the temporal associations between IBD and CNO we used Cox regression. We compared clinical data for IBD patients with CNO (IBD+CNO) and the IBD patients without CNO.

RESULTS

We identified 8244 children with IBD and 82 400 non-IBD comparators. At IBD diagnosis, CNO had been diagnosed in 0.13% (11/8244) of the IBD cohort and 0.03% (26/82 400) of the non-IBD comparators. During follow-up, 13 additional CNO cases occurred in the IBD cohort and 22 in the non-IBD comparators (adjusted hazard ratio = 5.87 [95% CI 2.95-11.66]). The prevalence of CNO among all prevalent children with IBD and prevalent matched non-IBD comparators December 31, 2022 was 0.48% (9/1885) and 0.02% (4/18 567), respectively. Median age at IBD diagnosis was lower in IBD + CNO compared to IBD without CNO (11 vs 14 years [-3 years, 95% CI -5 to -1]). Extraintestinal manifestations (except CNO) were more frequent in IBD + CNO (62% vs 21%, P < .0001). Treatment with biologics was more common in the IBD + CNO group (78% vs 44%, P = .004), prescribed for IBD and/or CNO.

CONCLUSIONS

We found a 6-fold increased risk of CNO in childhood-onset IBD compared to non-IBD comparators. Patients with IBD + CNO are characterized by younger age at IBD onset, more frequent extraintestinal manifestations, and higher usage of biologics.